Chables kellhee



U ITED STATE PATENT OFFICE.

CHARLES KELLNER, OF GOERTZ, AUSTRIA-HUNGARY.

METHOD OF sizme PAPER.

SPECIFICATION forming part of Iietters Patent No. 352,759, dated November 16, 1886.

Application filed April 23 1886. Serial No. 199,888.

To all whom it may concern: I

Be it known that 1, CHARLES KELLNER, of Goertz, in the Empire of Austria-Hungary, have invented certain new and useful Improvements in Methods of Sizing Paperfof which the following is a specification.

This invention relates to an improved pro-' cess of sizing paper, whereby the paper is not liable to assume a yellowish tint, as it does when sized in the ordinary manner.

Theinvention is specially designed for sizing paper made from ground wood pulp and sulphite cellulose, so that it assumes and retains a clear white color. .The brownish-yet low tint which the'paper made from wood pulp assumes after a certain time is caused by the size employed, which is produced by the precipitation of ordinary resin soap wit-h aluminium sulphate.

paper by mixing the pulp, first, with a resin soap and precipitating the same with a sulphite salt-such as magnesium or aluminium sulphite, or calcium, magnesium, or aluminium bisu1phite-or first with a sulphite salt and then with a resin soap.

In carrying out myinvention ordinary colophony may be used in making resin soap therefrom, which soap is mixed'with the pulp, after which one of the sulphite salts mentioned is added. The sulphite salts are lower in price than aluminium sulphate, and havethe further advantage that,-owing to the bleaching action of the sulphurous acid; the paper assumes and retains a perfectly White color, without being liable to change to a yellowish tint. The pro- My invention consists of a process of sizing (No specimens.)

.of the sulphurous acid the wood pulp contained in the paper-is rendered whiter and prevented from assuming a yellowish color, either on the drying-cylinders or later, because the sodium sulphite, which is formed by the resin soap, resists any tendency to reduction; thirdly, in the presence of the sulphurous acid the resin size is precipitated even from inferior, and consequently cheaper, resin soapv in a nearly colorless or whitish color; 7 fourthly, the sulphite cellulose. is continually kept in contact with salts which, by their reduoing tendency, prevent the coloring of the resin size; and fifthly, the sulphite combinations act simultaneously as bleaching agents, so asto dispense with the necessity of bleaching with chlorine. I

Having thus described my invention, I claim as new and desire to secure by Letters Patent- The process herein'described of sizing paper, which consists in mixing resin soap with the pulp and precipitating the resin size by asulphite salt, substantially as set forth.

In testimony thatl claim the foregoing as my invention I have signed'my name in pres ence oftwo subscribing witnesses.

, CHARLES KELLNER. Witnesses: GEORGE MARTIN,

J OSEF HEIDLY. 

